Feeding mechanism for sewing machines



July 20, 1943. F. PARRY FEEDING MECHANISM FOR SEWING'MACHINES 2 Sheets-Sheet 1 Filed Dec. 1l, 1941 July 20, 1943. F, PARRY` 2,324,873

FEEDING MECHANISM FOR SEWING MACHINES Filed Dec. 11, 1941 2 sheets-sneer, 2

Patented July 20, 1943 F EEDIN G MECHANISM FOR SEWING MACHINES Frank Parry, Bridgeport, Conn., assigner to The' Singer Manufacturing Company,

Elizabeth,

N. J., accrporation of New Jersey Application December 11, 1941,' Serial No. 22,482

Claims. (Cl. 11E-215) This invention relates to improvements in work-feeding mechanisms for'sewing machines and more particularly for zigzag lock-stitch sewing machines having an endwise reciprocatory and laterally vibratory needle, together with a loop-taker rotating in a plane substantially parallel to the plane of needle-vibration.

A primary object of the present invention is to provide in a zigzag lock-stitch sewing machine a feeding mechanism affording the necessary clearance to gain ready access to the loop-taker for replenishment of its thread-supply and for the employment of under bed attachments and auxiliary mechanisms.

The invention has also for its objects to provide a compactly arranged sewing machine feeding mechanism of sturdy construction and lending itself to high-speed operation of the sewing machine.

Other and more specific objects of the invention will be apparent from the following description and claims.

ing movements by the usual spring-.depressed presser-foot I6. Operating through the throatplate needle-slot I4 is a vertically reciprocatory and laterally vibratory needle I'Iwhich may be actuated by any usual or suitablemechanism (not shown), whereby the plane of lateral vibration of the needle is transverse to the line of feed of the work.

Complemental to the needle Il in the formation of zigzag lock-stitches is a forwardly open looptaker I8 of the rotary hook type having its axis of rotation extending horizontally crosswise of the bed-plate I 0 and substantially parallel to the line of feed, whereby the plane of rotation of the loop-taker is substantially parallel to the plane of needle-vibration. The loop-taker I8 is prefer-A The invention consists in the devices, combinav tions and arrangements Vof parts-hereinafter described in `connection with the accompanying drawings, which illustrate a preferred embodi-` s".

ment of the invention and in which:

Fig. 1 is a front side elevation of the bed mech anism of a sewing machine containing the present improvement, the work-supporting plate'of the bed-frame being shown in vertical section. Fig. 2 is a front end elevation of the feeding mechanism, a portion of the work-support being shown in transverse vertical section. Fig. 3 is a top plan view of the feeding mechanism, with the work-supportvpartly broken away and with the bed-frame shown in horizontal section. Fig. 4 is a bottom plan view of the machine. Y Fig. 5 is a vertical transverse section taken substantially on the line 5-5 of Fig. 1 and showing the feed-ad- Vance actuating connections. Fig. 6'is a vertical transverse section taken substantially on the line 6 6 of Fig.v 1 and showing the connectio-ns with the feed-lift actuating eccentric.

'Referring to the drawings, the sewing machine has a frame including a work-supporting bedplate I Il and a bracket-arm I I rising from one end of the bed-plate I0. Suitably secured upon the bed-plate IU is the usual throat-plate I2 provided with ieed-slots, as I3, and with a needle-r slot I4 which is elongated lengthwise of the bedplate lil.' Operating through the feed-slots I3 is a feed-dog I5 actuated, as hereinafter described, to advance the work crosswise ofthe bed-plate;

the feed-dog I5 being opposed in its work-engagably disposed entirely rearward of the path of needle-reciprocation and is actuated to perform two rotations for each complete endwise reciprocation of the needle Il; said loop-taker I8 being constructed to cast needlethread loopsl about a thread-carrier I9 journaled 'in the loop-taker and suitably restrained against rotation therewith. l

The loop-taker I 8 is carried bya shaft20 eX- tending rearwardly vfrom the loop-taker and l horizontally journaled in suitable bearings provided in a chambered casing 2| depending from the'bed-plate I6; said casing 2| being closed by an end-cover plate 22 detachably securedto the casing by screws, as 23, whereby the casing is adapted to contain a supply Vof lubricant. Carried by the loop-taker shaft 20, within the casing 2| and between the ends of said shaft 20, is a spiral pinion 24 engaged by a spiral driving gear 25 also disposed within the casing 2| and adapted to dip into a supply of lubricant within said casing. The driving gear 2,5 is suitably secured upon a horizontally disposed bed-shaft 26 extending lengthwise of the bed-plate I 0 and located-at the rearward side of the plane of rotation of the loop-Y taker. The bed-shaft 26 is rotatably jo-urnaled in a bearing-bushing 21 carried by the casing 2`| said shaft 26 being also journaled between -its ends in a bearing-bushing 28 secured in a lug 29 depending from the bed-plate I 0. vAt its end opposite tothe drivingV gear 25, the bed-shaft 26 Y :sesY

is journaled in aV ball-bearing 30 supported by a lug 3| depending from the bed-plate I0. Adjacent the 'lug 3|, the bed-shaft 26 carries a beltpulley 32 which'is driven Vby a clip-belt 33 in timed relation so that the bed-shaft 26 performs one rotation for eachlcomplete needle-reciprocation. f Y

The feed-dog I5 derives its work-advancing movements from the bed-shaft 26 by means of compactly arranged actuating mechanism providing for accurately positioning the feed-dog I lengthwise of the throat-plate feed-slots |3 and affording ready access to the loop-taker for replenishment of its thread-supply. To this end, the feed-dog l5 is suitably secured by screws 34 upon the forward end of a horizontally disposed feed-bar 35. 35 has a. horizontally apertured boss 3B pvotally mounted upon a stud-pin 31 disposed substantially parallel to the bed-shaft 26. One end of the stud-pin 31 is carried by the upper end of an arm 38 of a feed-rocker 39 disposed at the rearward side of the plane of rotation of the looptaker. The stud-pin has its reduced and threaded opposite end secured by a nut 40 in the upper end of a second arm 4| of the feed-rocker 39. The lower end of the feed-rocker 39 is pivotally mounted upon pintles 42, one of said plntles belng adjustably secured to the casing 2lA and the other plntle being adjustably secured to the bedlug 29. The pintles 42 support the feed-rocker 39 for movement about an axis parallel to the axis of rotation of the bed-shaft 28.

The feed-bar 35 is lengthwise provided with a guide-slot 43 disposed under the feed-dog i5, in which guide-slot is slidably disposed a pivotblock 44 carried by the forward free end of a short feed-lift crank-arm 45. The crank-arm 45 has a split hub clamped by a screw 46 upon one end of a feed-lift rock-shaft yIIT disposed substantially parallel to and forwardly of the bed-shaft 2B. As illustrated in the drawings, the rock-shaft 41 is, nevertheless, disposed at the rearward side of the vertical plane of rotation of the loop-taker la between said plane and the axis 42 of the feed-rocker 39. The feed-lift rockshaft 41 is Journaled in a bearing-lug 48 depen-dine from the bed-plate in front of the oedshait 26; said rock-shaft 41 being also Jcurnaied in the bearing-lug 29 to extend slightly beyond said bearing-lug. Adjustably clamped by a screw 4S upon the end of the rock-shaft 41 adjacent the bearing-lug 23 is the split-hub of a downwardly extending crank-'arm tu. The free end ofthe crank-ann 50 is connected by a pivot-bolt 5| to the forward end of a short pitman 52 having a strap 53 embracing a feed-lift eccentric 54 carried by the bed-shaft 28. Preferably, a roller-bearing S5 of the needle-roller type is interposed between the pitman-strap 53 and the eccentric 54.

In order to impart work-advancing and'return movements to the feed-dog i5, the bed-shaft 26 is provided'with an adjustable reed-advanoe-eccentric 56 carried by the bed-shaft between the casing 2| and the bearing-lug 23. The eccentric 56 is structurally similar to the adjustable eccentric more fully illustrated and described in the U. S. Patent No. 2,128,031, August 23, i938, W. Myers. In general, the eccentric 56 is carried by a guide-plate 51 shiftable diametrically of the shaft 28 in a suitable gnideway provided in a driver-member 58 fast upon the shaft 2G. An adjusting-member 59 disposed loosely upon the shaft 2l and suitably spring-pressed into engagement with the driver-member 5B has ya camtrack (not shown) entered 'by a stud 80 extending from the guide-plate 51. The hub of the adjusting-member 5S has a peripheral stop-notch 6| adapted to be entered oy one end of a springretracted datent-pin 62 endwise movable horizontally in a -suitable aperture provided in the bed-lug 48. The forward end of the detent-pin At its rearward end, the feed-bai' 62 is adapted to be engaged by an arm 63 depending from one end of a horizontally disposed spindle 64 supported for rocking movements in the bed-lugs 48 and 29. At its opposite end, the spindle 64 carries a flattened arm 65 positioned to be engaged by a spring-retracted plunger-pin Se extending vertically through an aperture in the bed-plate I0 so as to be accessible from the upper side of said bed-plate. When the plunger-pin 8S is depressed to cause the detent-pin G2 to enter the stop-notch 6| of the adjusting-member 59, the latter is held against rotation with the shaft 26. When the shaft 25 is now turned, the guideplete 51 is shifted diametrically in the guideway of the driver-member 58 and the eccentric 56 is thereby adjusted as to eccentri-city.

The eccentric 58 is embraced by the strap 61 cf a short pitman 68; it being preferred to interpose a needle-roller bearing 69 between the eccentric 58 and the pitrnan-strap 81. The pitrnan 68 extends horizontally forwardly from the bedshaft 26, and the forward end of said pitrnan is connected by a pivot-bolt 18 to the lower cnd oi a dcpendingcrank-a-rm 1|. The crank-arm 1| has a sleevehub 12 pivotally embracing the feedlift rock-shaft 41, whereby said rock-shaft 41 constitutes the fulcrlim of the crank-arm 1|. Adjustably clamped by a screw 'I3 upon the hub 12 of the crank-arm 1| is the split hub 14 of a crank-arm 15 extending upwardly from the rockshait 41 and oppositely to the crank-arm 1|. The crank-arms 1l and 15 are therefore coaxially ulcrumed upon the feed-'lift sha-ft 41 and together comprise a two-armed lever having the arms thereof angulariy adjustable relatively to eachother. The crank-arm 1B is pivotally connected, by a pivot-bolt 16 to one end of a link 11. At its opposite end, the link 11 has a sleeve 18 pivotally embracing the stud-pin 31 of the feedrocker, between the boss 86 ofthe feed-bar and the arm 4| of the feed-rocker.

It will be noted from Fig. 5 of the drawings that the axes of the rock-shaft 41 and the feedrocker 39 are not only substantially parallel, but also that they are disposed at substantially the same level. It will be further noted that the effective lengths of the arm 1l and the feedrocker arms 38, 4|, are Substantially equal, whereby a parallel-link motion effect is obtained. The described feedingfmechanism is therefore very compact in its 'arrangement of the part-s thereof-rearwardly of the vertical plane of rotation of the loop-taker |8. Ready access to the loop-taker for thread-replenishment purposes is therefore aiorded and the necessary clearance is provided under the bed-plate in front of the loop-taker and feed-mechanism for employment of auxiliary devices when desired. The Acompactly arranged feeding mechanism also lends itself to high speed operation.

By relative angular adjustment of the leverarms 1| and 15, the feed-dog l5 may be readily repositioned endwise of the throat-plate .feedsiots I3 without varying the height oi' the feeddog and without changing the plane of the leeddog teeth with respect to the plane of the worksupport. Y

As illustrated in Figs. 5 and 6 of the drawings, the bed-shaft 26 is longitudinally provided witn a bore 19 open at the end of said shalt disposed within the casing 2|, which casing houses tbe loop-taker driving gears and also serves asa lubricant-reservoir. Loosely disposed in the' bed-shaft bore 13 is a rod 80 ,protruding slightly from the shaft 26 within the casing 2|.

In the operation of the machine, lubricant splashed by the driving gear 25 lodges upon the protruding end of the rod 8E and is conducta lengthwise of the shaft-bore I9 for delivering lubricant to the needle-roller bearings 55 rand E9, in the manner more fully illustrated and described in the U. S. Patent of S. Zonis, No. 2,267,581, Dec. 23, 1941.

Having thus set forth the nature of the invention what I claim herein is:

1. Feeding mechanism for sewing machines having a frame including a work-support, a work-advancing feed-dog operating through said work-support, a feed-bar carrying said feeddog and disposed below said work-support, a feed-rocker disposed below said work-support and pivotally connected to said feed-bar, a feedlift rock-shaft disposed below said work-support and operatively connected to said feed-bar for imparting work-engaging and disengaging movements to said feed-dog, a rotary actuating shaft disposed below said work-support and substantially parallel to said rock-shaft, operative connections with said rotary shaft for actuating said rock-shaft, a feed-advance lever fulcrumed coaxially of said rock-shaft, a link connecting said lever to said feed-rocker independently of said feed-bar, an actuating eccentric carried by said rotary shaft, and a pitrnan actuated by said eccentric and operatively connected to said lever for imparting work-advancing and return movements to said feed-dog.

2. Feeding mechanism for sewing machines having a frame including a work-support, a work-advancing feed-dog operating through said work-support, a feed-bar carrying said feed-dog and disposed below said work-support, a feedrocker pivotally connected yto said feed-bar, a feed-lift rock-shaft disposed below said worksupport and operatively connected to said feedbar for imparting work-engaging and disengaging movements to said feed-dog a rotary actuating shaft disposed below said work-support and substantially parallel to said rock-shaft, operative connections with said rotary shaft for actuating said rock-shaft, a feed-advance lever fulcrumed coaxially of said rock-shaft, said lever having a pair of arms adjustable relatively to each other, a link connecting one of the arms of said lever' to said feed-rocker, an actuating eccentric carried by said rotary shaft, and a pitman actuated by said eccentric and operatively connected to the other arm Vof said lever.

3. Feeding mechanism for sewing machines, comprising, a work-advancing feed-dog, a feedbar carrying said feed-dog, a feed-rocker pivotally connected to said feed-bar, a feed-lift rock-shaft disposed substantially parallel to the fulcrum-axis of said feed-rocker, a crank-arm carried by said rock-shaft and operatively connected to said feed-bar for imparting workengaging and disengaging movements tol said feed-dog, a lever fulcrumed upon said rockshaft and having a pair of oppositely directed arms secured together for angular adjustment relatively to each other about the longitudinal axis of said rock-shaft, one of the arms of said lever being disposed substantially parallel to said feed-rocker, a link pivotally connected at its opposite ends to said feed-rocker and to the lever-arm parallel therewith, a rotary actuating shaft, a feed-advance eccentric carried by said shaft and operatively connected to the other arm of said lever for imparting work-adv work-support for'rotation in a plane substantially parallel to the plane of needle-vibration, looptaker actuating means including a rotary shaft disposed below said work-support at one side of the plane of needle-vibration, a feed-dog operating through said work-support for advancing work crosswise `ofsaid plane of needle-vibration,

arfeed-bar Carrying said feed-dog, a feed-lift.

rock-shaft disposed below said work-support at the rotary shaft side -oiY said plane of needlevibration, means connected to said rotary shaft for actuating said rock-shaft. operative connections between said rock-shaft and feed-bar for imparting work-engaging and disengaging movements to said feed-dog, and. operative connections between said rotary shaft and said feed-bar for imparting work-advancing andl return movements to said feed-dog. i

5. In a sewing machine having a frame including a work-support, in combination, an endwise reciprocatory and laterally vibratory needle, a loop-taker complemented to said needle' in the formation of stitches and disposed below said work-support for rotation in a plane substantially parallel to the plane of needle-vibration, looptaker actuating means including a rotary shaft disposed below said work-support for rotation about an axis transverse to the axis of rotation of the loop-taker, a feed-dog operating through said Work-support; for'advancing work crosswise of said plane of needle-vibration, a feed-bar carrying said feed-dog, a feed-lift rock-shaft disposed below said work-support and substantially parallel to said rotary shaft,'saidrockshaft being located between said rotary shaft and said plane of rotation or the loop-taker, means connected to said rotary shaft for actuating said rock-shaft, operative connections between said rock-shaft and said feed-bar for imparting workengaging and disengaging movements to said feed-dog, and operative connections between said rotary shaft and'said feed-bar for'imparting work-advancing and return movements to said feed-dog.

6. In a-sewing machine having a frame including a work-support, in combination, an'endwise reciprocatoryan'd laterally vibratory needle, a loop-taker complemental to said needle in the formation of stitches and disposed below said work-support for rotation in a plane substantially parallel to the plane of needle-vibration, looptaker actuating means including a rotary shaft disposed below said work-support for rotation about an axis transverse to the axis of rotation of the loop-taker, a feed-dog operating through said work-support for advancing work crosswise of said plane of needle-vibration, a feed-bar carrying said feed-dog, anoscillatory feed-rocker disposed below said work-support and pivotally connted to said feed-bar, a feed-lift rock-shaft disposed below said work-support; substantially parallel to the Vaxis of oscillation of said feedrocker and between said feed-rocker and said plane of rotation of the loop-taker, means connected to said rotary shaft for actuating said rock-shaft, operative connections between said rock-shaft and said feed-bar for imparting Workengaging and disengaging movements to said feed-dog, and operative connections between said rotary shaft and said feedbar for imparting work-advancing and return movements to said feed-dog. Y

7. In a sewing machine havinB a frame in cluding a. work-support, in combination, an end wise reciprocatory and laterally vibratory needle, a loop-taker complemented to said needle in the formation of stitches and disposed below said worksupport for rotation in a plane substantial 1y parallel to the plane of needle-vibration, loop taker actuating means including a rotary shaft disposed below said work-support-I fcr rotation about an axis transverse to the axis of rotation of the loop-taker, a feed-dog operating through said work-support for advancing work crossewise of said plane of needle-vibration, a feed-bar carrying said feed-dog. an oscillatory feed-rocker disposed below said work-support and pivotally connected to said feedbar, a fe`edlift mcbshaft disposed below said work-support substantially parallel to the axis of oscillation of said feedrocker and between said feed-rocker and said plane of rotation of the loop-taker, means ccnnected to said rotary shaft for actuating said rock-shaft, operative connections between said rock-shaft and said feed-bar for imparting workengaging and disengaging movements to said leed-dog, a two-armed lever fulcrumed coaxially of said rock-shaft, a feed-advance eccentric carried by said rotary shaft, a. pltman having at one end a strap embracing said eccentric and having its other end pivotally connected to one arm of said lever, and a link connecting the other arm of said lever to said feed-rocker for imparting work-advancing and return movements to 'said feeddog.

8. In a sewing machine having a frame including a work-support, in combination, an endwise reciprocatory and laterally vibratory needle, a loop-taker complementa! to said needle in the formation of stitches and disposed below said work-support for rotation in a plane substantially parallel to the plane of needle-vibration loop-taker rotating means including a rotary shaft disposed below said work-support at the loop-taker' side of the plane of needIeWibmtiQn, a feed-dog operating through said work-support for advancing work crosswise of said plane of needle-vibration, a feed-bar carrying said feed-L dog, a feed-rocker pivotally connected to said feed-bar and disposed at the loop-taker side of said plane of needle-vibration, a feed\lift rock shaft disposed below said work-support at the rotary-shaft side of said plane of needle-vibra tion, means connected to said rotary shaft for actuating said rock-shaft, a crank-arm carried by said rock-shaft and operatively connected to said feed-bar for imparting workengaging and disengaging movements to said feed-dog, and operative connections between said rotary shaft and feed-rocker at the loop-taker side of said plane of needle-vibration for imparting work-advancing and re` turn movements to said feed-dog.

9. In a sewing machine having a frame including a. work-support, in combination, an end wise reciprocatory and laterally vibra-tory needle, a. loop-taker complemental to said needle in the formation of lock-stitches and disposed below said worlbsupport for rotation in a plane sul stantially parallel to the plane of needle-vibration, loop-taker rotating means including a rotary shaft disposed below said Workesupport at one sido of the plane of needle-vibration, a feeddcg operating through said worksuppoit for advancing Work crosswise of said pla-ne of needlevibration, a feed-bar carrying said feed-dog; a feed-rocker pivotally connected to said iecdibar and disposed at the rotary shaft side of said plane of needle-vibration a feeddift rock-shaft disposed below said work-support at the rotary shaft side of said plano of needle-vibration, said rockshait being substantially parallel to said rotary' shaft and to the fulcrum-axis of said iecdvocl:M cr, a ffccd-lift eccentric carried by said ro shaft and connected to actuate said rock-sha operative connections between said rc-ck-sliait and feodbar for imparting worin-engaging and disengaging movements to said feed-dog, a lever iulcrumed upon said feed-lift rocl`rsliait, a link connecting said lover to said ieederocker, and a feed-advance eccentric carried by said rotary shaft and connected to said lever for iinpai ng work-advancing and return movements to 'salti iced-dog.

i0. In a sewing machine having a frame including a work-support, in combination, an cl`1d wise reciprocatory and laterally vlbratory needle, s loop-taker complementari to said needle in the formation of lock-stitches and disposed below said work-support for rotation in a plane omai-- lei to and at the rearward side oi the plane ci' needle-vibration, a loop-taker carrying shaft ex'- tenuing crosswlse of said work-support and disposed at the rearward side of said plane ci needle-vibration, a rotary-actuatng shaft disposed below said work-'support to extend iene-tnn wise thereof at the rearward side of said plano of needle-vibration, driving and driven 'gears conn nesting said Shafts, a feed-dog operating 'through said work-support for advancing work crosswise of said piane of neediewlbration, a feedbar carrying said feed-oog, a feed-lift roelmhait disposed below said wcrlcsu'pport rearward or the plane of -needlevibration and substantialiy parallel to said rotary shaft, connections with said rotary shaft for actuating said rock-shaft, operative connections between said rock-shaft and feed-bar for imparting work-engaging and dlsengaging movements to 'said feed-dog, 'a feedadvance lever fulcrumed coaxaliy of said ionic shaft and having a pair of opposit'ely directef arms secured together for angular adjustment relatively to each other about the longitudinal axis `of said rock-shaft, operative connections with said rotary shaft rand one arm of said lever for rocking said lever, and Operative connections between the other arm of said lever and said feedbar for imparting workandvancing and return movements to said feed-dog'.

FRANK PART; 'f 

